Some basic suggestions:
Obviously try restarting the My Cloud to see if the error clears.
If any media has been added to the My Cloud recently remove the media, its possible Twonky is choking on a media file.
If the My Cloud firmware has been modified in any way, like to fix sleep issues or add modules, remove those modifications and see if the problems clears.
Try a 4 second reset and if that doesn’t work a 40 second system restore.
Oh well. It ran well for about 4 hours then back to its sluggish normal. It takes 70 seconds to display the dashboard splash screen and another 5 to 10 minutes to populate the form. It takes anywhere from 30 seconds to several minutes to populate a Windows Explorer query into any public or private folder regardless of the data volumes.
Clearly there are latent issues buried in this OS that seem to find a trigger (but what?) that sends the OS into a spin.
I’m looking at options for fixing or replacing it.